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Article Citation - WoS: 1Citation - Scopus: 1Characterization of Pbmo0.3w0.7< Crystal: a Potential Material for Photocatalysis and Optoelectronic Applications(Wiley-v C H verlag Gmbh, 2024) Isik, Mehmet; Gasanly, Nizami MamedPbMo0.3W0.7O4 semiconductor crystal, which contains the balanced ratios of Mo and W, is grown for the first time by Czochralski method. The structural and optical properties of the crystal are investigated in detail in the present study. Structural analysis shows that crystal has tetragonal structure like PbMoO4 and PbWO4 compounds. The optical characteristics are studied by transmission, Raman, FTIR and photoluminescence methods. The bandgap energy is found to be 3.18 eV, and the positions of the conduction and valence bands are determined. The vibrational characteristics are studied by means of Raman and FTIR spectroscopy techniques. Photoluminescence spectrum presents three peaks around 486, 529, and 544 nm which fall into the green emission spectral range. Taking into account the properties of the compound, it is stated that PbMo0.3W0.7O4 (or Pb(MoO4)(0.3)(WO4)(0.7)) has the potential to be used in water splitting applications and optoelectronic devices that emit green light.Article Citation - WoS: 75Citation - Scopus: 80Unique Ligand-Based Oxidative Dna Cleavage by Zinc(ii) Complexes of Hpyramol and Hpyrimol(Wiley-v C H verlag Gmbh, 2007) Maheswari, Palanisamy Uma; Barends, Sharief; Oezalp-Yaman, Seniz; de Hoog, Paul; Casellas, Helene; Teat, Simon J.; Reedijk, JanThe zinc(II) complexes reported here have been synthesised from the ligand 4-methyl-2-N-(2-pyridylmethyl)aminophenol (Hpyramol) with chloride or acetate counterions. All the five complexes have been structurally characterised, and the crystal structures reveal that the ligand Hpyramol gradually undergoes an oxidative dehydrogenation to form the ligand 4-methyl-2-N-(2-pyridylmethylene)aminophenol (Hpyrimol), upon coordination to Zn-II. All the five complexes cleave the phi X174 phage DNA oxidatively and the complexes with fully dehydrogenated pyrimol ligands were found to be more efficient than the complexes with non-dehydrogenated Hpyramol ligands. The DNA cleavage is suggested to be ligand-based, whereas the pure ligands alone do not cleave DNA. The DNA cleavage is strongly suggested to be oxidative, possibly due to the involvement of a non-diffusible phenoxyl radical mechanism. ne enzymatic religation experiments and DNA cleavage in the presence of different radical scavengers further support the oxidative DNA cleavage by the zinc(II) complexes.Article Citation - WoS: 2Citation - Scopus: 2Investigation of Tungsten-Based Seleno-Chevrel Compounds With Different Compositions for Efficient Water Splitting(Wiley-v C H verlag Gmbh, 2023) Dag, Tugce Sevinc; Surucu, Gokhan; Gencer, Aysenur; Surucu, Ozge; Ozel, Faruk; Ciftci, YaseminThis study investigates the photocatalytic water splitting performance for NixW6Se8(x=1,2,3,4)${\mathrm{N}}{{\mathrm{i}}_{\mathrm{x}}}{{\mathrm{W}}_6}{\mathrm{S}}{{\mathrm{e}}_8}\;( {x = 1, 2, 3, 4} )$ Chevrel phases with the chemical formula M(x)Mo(6)Ch(8), where M is a metal and Ch is a chalcogen, with x being 0, 1, 2, 3, or 4. Density Functional Theory (DFT) is used to study the NixW6Se8(x=1,2,3,4)${\mathrm{N}}{{\mathrm{i}}_{\mathrm{x}}}{{\mathrm{W}}_6}{\mathrm{S}}{{\mathrm{e}}_8}{\mathrm{\;}}( {x = 1, 2, 3, 4} )$ Chevrel phases, which includes earth-abundant elements for this specific study as an essential consideration for photocatalytic water splitting. The electronic properties are calculated for the NiW6Se8 and Ni2W6Se8 compounds with thermodynamical, mechanical, and dynamic stabilities. For photocatalytic water splitting, the band gaps below 1.23 eV are excluded, and the conduction and valence band levels are determined to examine the reduction and oxidation potentials for efficient photocatalytic water-splitting materials. An examination of the selected band gaps, along with the conduction and valence band levels, reveals that NiW6Se8 is suitable for both reduction and oxidation reactions; whereas, Ni2W6Se8 is a convenient material only for the reduction reaction. This is the first attempt, as far as the literature reveals, to study Chevrel phases in detail and to identify a suitable compound for photocatalytic water splitting.Article Citation - WoS: 1Citation - Scopus: 1P-tlgases/N-bn Heterojunction as a Microwave Filter and as a Photovoltaic Device(Wiley-v C H verlag Gmbh, 2015) Qasrawi, Atef F.; Omar, Ahmad; Azamtta, Ala' M.; Gasanly, Nizami M.In this work, a p-n junction made of p-type TlGaSeS and n-type boron nitride (BN) is investigated and characterized. The bilayer was studied by means of capacitance-voltage characteristics, current-voltage characteristics and Bode signal and photovoltaic effect diagnostics. It was observed that the pTlGaSeS/n-BN bilayer exhibits negative capacitance values in the frequency range of 30-80 MHz. For an ac signal of 30 MHz, the built-in voltage and density of noncompensating carriers for the device are found to 1.06 eV and 1.72 x 10(12) cm(-3), respectively. The characteristic Bode curve analysis indicated that the bilayer behaves as a lowpass microwave filter that blocks all signals of frequencies larger than 1.28 GHz. The time constant for this device is 124 ps. In addition, the p-TlGaSeS/n-BN junction exhibited a well-pronounced photovoltaic effect. The device showed switching properties from low to high-current injection at a particular switching voltage. The switching voltage is sensitive to the light energy and intensity. It decreased systematically with increasing light intensity and energy. The device responsivity is similar to 7.64mAW(-1). The filtering and photovoltaic properties of the device suggest its use as an optoelectronic switch and as a microwave filter being suitable for multipurpose operations. (C) 2014 WILEY-VCH Verlag GmbH & Co. KGaA, WeinheimConference Object Citation - WoS: 9Citation - Scopus: 13Design of a Hybrid Photovoltaic-Electrolyzer Fuel Cell System for Developing Solar Model(Wiley-v C H verlag Gmbh, 2015) Devrim, Yilser; Pehlivanoglu, KubraThe world's fossil fuel energy reserves have rapidly decreased, while the energy demand has increased due to industrial growth, population growth, and technology advances, all of which affect the environment by the production of greenhouse gases. Alternative energy sources such as solar, hydrogen, etc. are attracting more attention as an alternative of fossil fuels. We present in this study hybrid photovoltaic (PV) panels/PEM electrolyzer/high temperature proton exchange membrane fuel cell (HTPEMFC) system used in off-grid application. The purpose of a hybrid system is to produce as much energy from alternative energy sources to ensure the load demand. Solar energy is used as primary source and a fuel cell is used as backup power. The hybrid system is designed and analyzed according to the new solar radiation model. Firstly a new solar model is developed to determine solar radiation on horizontal surface. After that solar radiation on tilted surface is obtained by using solar radiation on horizontal surface model for PV panel calculations. The hybrid system is modelled and the obtained results presented and discussed. (C) 2015 WILEY-VCH Verlag GmbH & Co. KGaA, WeinheimArticle Citation - WoS: 2Citation - Scopus: 1Direct Detection of Viral Infections From Swab Samples by Probe-Gated Silica Nanoparticle-Based Lateral Flow Assay(Wiley-v C H verlag Gmbh, 2024) Durdabak, Dilara Buse; Dogan, Soner; Tekol, Serap Demir; Celik, Caner; Ozalp, Veli Cengiz; Tuna, Bilge GuvencPoint-of-care diagnosis is crucial to control the spreading of viral infections. Here, universal-modifiable probe-gated silica nanoparticles (SNPs) based lateral flow assay (LFA) is developed in the interest of the rapid and early detection of viral infections. The most superior advantage of the rapid assay is its utility in detecting various sides of the virus directly from the human swab samples and its adaptability to detect various types of viruses. For this purpose, a high concentration of fluorescein and rhodamine B as a reporting material was loaded into SNPs with excellent loading capacity and measured using standard curve, 4.19 mu mol & sdot; g-1 and 1.23 mu mol & sdot; g-1, respectively. As a model organism, severe acute respiratory syndrome coronavirus-2 (CoV-2) infections were selected by targeting its nonstructural (NSP9, NSP12) and envelope (E) genes as target sites of the virus. We showed that NSP12-gated SNPs-based LFA significantly outperformed detection of viral infection in 15 minutes from 0.73 pg & sdot; mL-1 synthetic viral solution and with a dilution of 1 : 103 of unprocessed human samples with an increasing test line intensity compared to steady state (n=12). Compared to the RT-qPCR method, the sensitivity, specificity, and accuracy of NSP12-gated SNPs were calculated as 100 %, 83 %, and 92 %, respectively. Finally, this modifiable nanoparticle system is a high-performance sensing technique that could take advantage of upcoming point-of-care testing markets for viral infection detections. Here, universal-modifiable probe-gated silica nanoparticles (SNPs) based lateral flow assay (LFA) is developed in the interest of the rapid and early detection of viral infections. The most superior advantage of the rapid assay is its utility in detecting various sides of the virus directly from the human swab samples and its adaptability to detect various types of viruses. The NSP12, NSP9, and E gene targets of CoV-2 were used as detection targets.image
